Previously, many types of lids and covers have been used in endeavoring to provide an effective means to either cover the top of a container or slide inside the container to cover the product. Many have developed covers for dry articles such as coffee, tobacco and sugar or liquids such as paint to prevent the hardened skin on the top. In most cases prior art has utilized some type of valve or simply vents to permit the air within the container to escape when applying the cover and to prevent a vacuum to be formed precluding removal.
A search of the prior art did not disclose any patents that possess the novelty of the instant invention; however the following U.S. patents are considered related:
U.S. Pat. No.InventorIssue Date1,978,025McGownOct. 23, 19342,172,457SchwartzSep. 12, 19392,726,012JensenDec. 6, 19533,784,051Shaw et al.Jan. 8, 19743,978,941BlessingOct. 26, 19764,723,674NunesFeb. 9, 19884,874,108ValasekOct. 17, 19895,213,230KralMay 25, 19935,339,981KralAug. 23, 1994Publication 2003/0190393Johnson et al.Oct. 9, 2003
McGown in U.S. Pat. No. 1,978,025 teaches a coffee can vacuum attachment which consists of a disc member formed of relatively thin flexible rubber with its center curving upwardly permitting insertion into a coffee can. A valve member having a handle on top is stretched slightly so that it lays flat against the disc and when lifted up from its seat the valve port is opened permitting air to enter or escape above the coffee in the can.
U.S. Pat. No. 2,172,457 issued to Schwartz is for a cover used in dispensing containers for dry articles such as tobacco, coffee, sugar and the like. The cover is made of plastic and is slightly resilient and has air tight sliding contact with the inner surface of the container. A vent is provided that permits air to escape when installing or removing the cover.
Jensen in U.S. Pat. No. 2,726,012 discloses a flavor-protecting coffee cover for vacuum packed coffee. The cover includes a handle and a disc having a diameter slightly smaller than the can with a number of small apertures in the top wall thought which air may flow when the disc is installed or moved upwardly.
Shaw et al. in U.S. Pat. No. 3,784,051 teaches a closure member sealingly movable in the container in contact with the contents excluding air above the surface of the contents.
U.S. Pat. No. 4,874,108 issued to Valasek is for a sealer used with containers. The sealing portion has a handle attached and is capable of covering the surface of the substance within the container. The sealer is a flexible membrane with an O-ring at its circumference. The handle portion is also flexible and has a shaft portion with a top extending above capable of fitting entirely with in the container and is not required to be fastened when the container lid is affixed thereon.
Kral in U.S. Pat. Nos. 5,213,230 and 5,339,981 disclose a paint can sealer for sealing the surface of the contents within a container. The sealer consists of a disc-like member having a centrally located upstanding hollow handle with a purge valve at the upper end. The purge valve has a closed position for preventing egress of air upwardly thru the hollow handle and a open position for air passage. The disc-like member is contoured to correspond with the shape of the interior of the container. The purge valve located within the handle may be manually pinched to open permitting an air flow from the lower surface of the device to atmosphere.
For background purposes and as indicative of the art to which the invention is related reference may be made to the remaining cited patents issued to Blessing in U.S. Pat. No. 3,978,941 and Nunes in U.S. Pat. No. 4,723,674